In exploring the scope and limitations of using the mold, Rhizopus nigricans, for the hydrolysis of racemic acetates to prepare chiral alcohols, we examined the products from the hydrolysis of a series of medium-ring 2-cycloalkenyl acetates. These substrates were chosen because of their similarity to a variety of plant and marine natural products. In order to increase the versatility of these chiral alcohols as synthetic intermediates, the 2-bromo derivatives, and both (E) and (Z) isomers of the parent allylic alcohols were employed as substrates for R. nigricans. In every case, except for 2-cyclodecenol, a chiral alcohol was formed and its absolute stereochemistry was established as R by chemical transformation into the corresponding dimethyl Alpha-acetoxydicarboxylate of known absolute stereochemistry. The chiral alcohols were then used to determine whether a recently proposed rule by Harada and Nakanishi, relating the signs of the c.d. bands of p-substituted benzoates of allylic alcohols with their absolute stereochemistry, could be employed for medium-ring allylic alcohols. These compounds exist in many more conformations than are available for the five-, six- and seven-membered analogues. Although the signs of the c.d. bands of p-bromobenzoates of the medium-ring esters differd from those of the five-, six- and seven-membered analogues it was possible to rationalize the change in sign with the Harada-Nakanishi rule and with information on the conformation calculated as the most stable for each ring system.